Artificial rock climbing walls placed in gyms create a controlled environment, including safety measures, that allows beginners to try out the sport of climbing and experienced climbers to practice their skills. A typical rock climbing wall contains T-nut screw inputs. The T-nuts allow for removable pieces called rock climbing holds to be set on the wall to create a climbing route of variable difficulty. The shape of the holds, their placement, and the curvature of the wall determine the difficulty of the route. Additionally, artificial rock climbing walls allow climbers to try different forms of climbing.
Depending on the height of the wall and the safety measures installed, a climbing route can be approached either by top rope, bouldering, or lead climbing techniques. Top rope climbing requires the use of a rope, used for the climber's safety, that runs from the climber through an anchor system at the top of the route down to a belayer at the foot of the route. Bouldering is the unassisted climbing of shorter walls that results in the climber either dropping a short distance or climbing to a safe platform at the end of a route. In certain gyms, lead climbing is possible but requires more equipment than top rope or bouldering. Like top rope, lead climbing requires the assistance of a rope and belayer, however, the rope is not fixed to an anchor system at the top of the wall. Instead, the climber brings the rope up as they climb and clips it to anchor points on the wall. These anchor points will catch the climber if they fall, but they do not aid in ascension process.
Lead climbing is split into the sub-categories of sport and traditional climbing. Both sub-categories follow the lead climbing process previously outlined, but the key difference is how the anchor points relate to the wall. In sport climbing, the anchor points are directly bolted to either a real rock or an artificial climbing wall. From the fixed bolts is a tether with a carabiner that clips the rope to the wall. Sport climbing is the most common form of lead climbing that is practiced on artificial walls. This is due to the abundance of T-nut screw inputs on artificial climbing walls that are used to bolt tethers along a climbing route.
In traditional lead climbing, the anchor points are not permanently fixed or bolted to the wall. Instead, the anchor points consist of removable protective gear that is placed on or into rocks. The removable protective gear operates by binding against the rock to hold its placement through friction. In the case of a fall, the removable gear will bind against the rock to catch the falling climber. If the removable gear does not properly engage or bind against the rock due to improper placement, it may slip out of place and will not serve as a protective measure. In this instance, the climber will continue to fall until the next lowest piece of removable protective gear engages.
Removable protective gear is comprised of two categories, active protection and passive protection. Active protection constitutes any removable gear that has an activating mechanism, such as pulling a lever, to cause the gear to expand. Active protection includes the cam-type protective gear. Passive protection constitutes any removable gear that does not have moving parts.
Traditional climbing is typically reserved for the outdoors where it can be placed in real rock. There remains a continuing need for artificial climbing holds, walls, and equipment for training and practicing lead climbing.